The invention is based on an internal combustion engine as generally defined hereinafter. It is known (European Pat. No. 0071179 A2, European Pat. No. 0071272 A2) for bypass conduits having adjustable slides to be associated with the spirally extending inlet conduits leading to combustion chambers in internal combustion engines, with the flows in the combustion chambers being variable via the adjustable slides. At low load and/or low rpm, the slides are at least partially closed, so that the inlet conduits, which terminate in a spiral, generate high spin in the combustion chambers as they are being filled, thereby accelerating the courses of combustion. At full load and/or low rpm the slides are opened wide, so that the spin is relatively low and the combustions cannot elapse so rapidly. Adjustment is effected by a slide position regulator, which is connected both to a set-point value transducer operating in accordance with operating parameters such as rpm and pressure in the inlet conduits and to an actual-value transducer coupled with the slide and measuring the orientation of the slide. However, optimal combustion courses come about only when parameters such as the dimensions of the inlet conduits of the engine and of the slides, engine and air temperature, humidity and the ignitability of the fuels agree precisely with the initial parameters upon which the ascertainment of optimal set-point values is based. Otherwise the engines operate at a higher level of fuel consumption and with increased wear, and more toxic exhaust gas components are produced.
In another known internal combustion engine (U.S. Pat. No. 4,285,310), two inlet conduits provided with inlet valves discharge into one combustion chamber. One of the inlet valves has a stroke drive means that is controlled by the vacuum in the inlet conduit. Different opening strokes are effected at the inlet valve depending on the magnitude of the vacuum. A change in the opening strokes results in different kinds of turbulence in the combustion chamber. The production of turbulence is promoted at low engine load, in order to accelerate the combustion processes or events. In this engine as well, differences in manufacture, aging of the system, fluctuations in environmental conditions, the properties of the fuel and mismatches of various fuels result in disadvantageous deviations from the most favorable turbulence in a particular case.